An advertiser of goods or services who wishes to target advertising to individuals or organizations that are likely to be more interested in the offered goods or services than the public in general, can today take advantage of electronic mail, i.e. so called e-mail, to send to perspective buyers an advertisement via a computer network such as the Internet. In such an advertising strategy, an advertiser would obtain a mailing list providing e-mail addresses of individuals or organizations that for one or another reason would reasonably be thought to be interested in the goods or services being offered by the merchant. The advantage to an advertiser of such an advertising strategy is that the advertiser typically does not pay to send an e-mail, although in the case of the Internet, the advertiser does have to pay typically a monthly fee for access to the Internet. The disadvantage is that since sending an e-mail costs essentially nothing, many people or organizations have, at least in the past, used e-mail to send messages or advertising with little regard for the likelihood that the recipient of the e-mail would be interested in the e-mail message. Such indiscriminate, unsolicited e-mailing is sometimes referred to as spam. Because of span, many people decline to open and read unsolicited e-mail, in recognition of the simple fact that the sender did not have to weigh the cost of sending the e-mail compared to the likelihood that the e-mail would be somehow worthwhile.
What is needed is a protocol for sending e-mail messages that could be used for advertising or to convey any other kind of message in such a way that a receiver of the e-mail would believe that the e-mail is more likely than not worth opening and reading.